<%@ page contentType="image/jpeg" import="java.awt.*,java.awt.image.*,java.util.*,javax.imageio.*" pageEncoding="utf-8"%>

<%!

    Color getRandColor(int fc,int bc)

    {
        Random random = new Random();

        if(fc>255) fc=255;

        if(bc>255) bc=255;

        int r=fc+random.nextInt(bc-fc);

        int g=fc+random.nextInt(bc-fc);

        int b=fc+random.nextInt(bc-fc);

        return new Color(r,g,b);

    }

%>

<%

    out.clear();                           /*这句针对resin服务器，如果是tomacat可以不要这句*/

    response.setHeader("Pragma","No-cache");

    response.setHeader("Cache-Control","no-cache");

    response.setDateHeader("Expires", 0);

    int width=60, height=20;

    BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

    Graphics g = image.getGraphics();

    Random random = new Random();

    g.setColor(getRandColor(200,250));

    g.fillRect(0, 0, width, height);

    g.setFont(new Font("Times New Roman",Font.PLAIN,18));

    g.setColor(getRandColor(160,200));

    for (int i=0;i<155;i++)

    {
        int x = random.nextInt(width);

        int y = random.nextInt(height);

        int xl = random.nextInt(12);

        int yl = random.nextInt(12);

        g.drawLine(x,y,x+xl,y+yl);

    }


    String sRand="";

    for (int i=0;i<4;i++){
        String rand=String.valueOf(random.nextInt(10));

        sRand+=rand;

        g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));

        g.drawString(rand,13*i+6,16);

    }

// 将认证码存入SESSION
    session.setAttribute("srand",Integer.parseInt(sRand));

    g.dispose();

    ImageIO.write(image, "JPEG", response.getOutputStream());

%>